Hey folks... I thought I'd come by and share a few thoughts as a former newsie for PSU back in its heyday.
First of all, being on staff of the largest and most popular PS fan site is an honor and a privilege. The community both within the staff and the larger fan base is really impressive, given the size of the game and the number of players. To be on staff at PSU is to hold a special place in the Planetside community.
That said, being a newsie at PSU is no cakewalk. Although Hamma has already noted that there is no specific time requirement, you should be willing to be available to post breaking news as quickly as you can. For me, this often included dodging out of class to find the nearest computer to post something that one of my news aggregators alerted me to. It also meant I spent a significant amount of free time trolling the various other fan sites, PS site, and PS official forums looking for news. In addition, I spent innumerable hours hanging out in PSU's IRC channel shootin' the breeze with my friends, the PSU community.
From time to time, you may also be tasked with writing up some how-tos, in-depth articles, or guides for various features or game pieces (like vehicles, certs, etc). You'll also be pulled in to assist in moderation and logistics whenever PSU or AGN hosts a large community event. Throughout your entire day, you'll need to be able to keep an eye on the PSU forums and IRC channel to make sure they're moderated properly and that community development is encouraged. And don't forget - you've gotta keep Hamma happy.
In a nutshell, being a newsie for PSU is a commitment that should be taken seriously. Be prepared to dedicate your time and efforts to the website and the community.
If you have any questions, please feel free to reach out and let me know.
-Strygun